Numerous devices are already known for separately storing two components which are to be mixed together extemporaneously on first use.
U.S. Pat. No. 4,936,446 discloses a device comprising a receptacle formed by assembling together a bellows and a flask having a neck. The bottom end of the bellows is snapped onto the neck of the flask, and its other end is provided with a dispensing endpiece. The neck of the flask is closed by a removable plug, and the flask and the bellows can thus separately contain two separate components for mixing together on first use of the device. The dispensing endpiece is screwed into a tapped orifice of a rotary drive member engaged on the neck of the flask and designed to exert force on the plug to put the two compartments into communication with each other on first use of the device. A closure cap is screwed onto the dispenser endpiece to close it. The drive member is shaped so as to prevent the user gripping the closure cap until the drive member has been rotated to displace the plug and put the flask into communication with the bellows. Displacement of the plug is accompanied by the bellows lengthening and by the closure cap emerging from the drive member, thereby making it possible to open the dispenser endpiece. Such a device is relatively complex and expensive to make. In particular, the bellows can be difficult to make, specifically if it is designed to contain a component whose nature restricts the materials that can be used for making the bellows, or indeed the manufacturing techniques that can be implemented.